There is a strong relationship between phonological awareness and reading. Intensive phonological intervention is often utilized in order to advance children who lag behind in reading achievement. Nevertheless, the neural mechanisms of reading improvement following behavioral intervention are still unknown. Although most intervention programs focus on children, it is believed that plasticity, and hence a basis to bring abut change in the nervous system, extends into adulthood. Therefore, there may be great potential for reading skill acquisition in adults, even if reading skills were not acquired during childhood because of the presence of developmental dyslexia. We propose a series of experiments to investigate the behavioral and physiological changes (measured with fMRI) resulting from intensive behavioral intervention using the Lindamood-Bell program with adult subjects. One group of the dyslexic individuals will receive a phonological-based experimental intervention program of the second group will receive a control intervention based on mathematical skill straining. All dyslexic individuals participating will have a persistent decoding deficit from childhood to the present and half of these dyslexic individuals will also demonstrate a persistent fluency deficit, as identified by poor naming speed. Response to intervention will be compared between these "double deficit" and "single deficit" groups, to identify behavioral and physiological differences in their responses to remediation. The results of these experiments will provide important new information about the neural mechanisms responsible for reading improvements in adults who have a persistent history of poor decoding and fluency.